The present invention relates to a video receiver used to receive audiovisual programs and data broadcast from a satellite, for example, and which is adapted to be connected to a home video display, such as a television, or other video, audio, and/or data output device.
Direct broadcast satellite systems (DBS) for broadcasting video, audio, data and other programming (herein sometimes referred to as program data) to a plurality of remote locations have been available to consumers for more than one year prior to the filing of this patent. An example is the DSS.RTM. system utilized by DIRECTV and USSB broadcasting services. Typical DBS systems generate satellite broadcasts which are received by relatively small satellite antennas (such as dishes) each of which is typically owned by an individual subscriber, disposed at locations such as a house or hotel, for example. The satellite antenna system is utilized in conjunction with a prior art receiver unit, which also includes a decoder adapted to be connected to a video or other output device (e.g. audio system or computer) and which provides decoded program data outputs to the output device.
In such known consumer systems, the satellite antenna of the receiver is initially oriented towards the geosynchronous satellite from which it is to receive broadcast program in a manual manner by the subscriber as described below. The subscriber determines the correct azimuth and altitude for their geographic location. This may be done by utilizing zip codes or latitude and longitude information. In known systems, the needed azimuth and altitude information may be obtained by entering the geographic information (e.g. zip code, or latitude and longitude). The receiver unit then accesses a lookup table stored in its internal memory to determine the azimuth and elevation angles to which the antenna should be oriented so that it points to the satellite, and displays those angles e.g. on the television to which the receiver unit is connected.
The subscriber then manually orients the satellite antenna to the azimuth angle specified by the receiver unit by using a compass, and to the elevation angle specified by the receiver unit by using a set of elevation angle markings, similar to the markings on a protractor, disposed on the satellite antenna support.
After the satellite antenna is initially oriented in the above manner, the subscriber may adjust its orientation by using a display, typically generated by the receiver unit for display on e.g. the television, related to the quality (e.g. signal strength and/or error rate, or other known quality measure or factor) of the broadcast program data received by the antenna. The subscriber accomplishes the adjustment by manually moving the satellite antenna in increments until the received quality of the received broadcast is maximized. Other systems provide alternative quality factor indicators (e.g. meters or variable flashing LEDs), but still require manual incremental adjustments.
It is presently known that receiver units of DBS systems of the type described above have been previously used on an airplane in combination with a steerable parabolic antenna for receiving the broadcast signal. To enable reception of the broadcast signal regardless of the location and attitude of the airplane, the orientation of the parabolic antenna is continuously varied based upon electronic signals generated by the airplane, such as signals representing latitude, longitude and altitude.
It is also known that receiver units of DBS systems have been previously used on a ship in combination with a steerable parabolic antenna for receiving the broadcast. To enable reception of the broadcast regardless of the location and attitude of the ship, the orientation of the parabolic antenna is continuously varied based upon e.g. the sensed signal strength of the broadcast signal and/or attitude of the ship.